Water tube for rock drills



July 4,1939.

J. E. RENFER WATER TUBE EOR ROCK DRILLS Filed Dec. 17, 1937 INVENTORPatented July 4, 1939 I 2,164,886

UNITED STATES PATENT OFFICE WATER TUBE FOR ROCK DRILLS John E. Renfer,Cleveland Heights, Ohio, assignor to The Cleveland Rock Drill Company,Cleveland, Ohio, a corporation of Ohio Application December 17, 1937,Serial No. 180,311

8 Claims. (01. 121-10) This invention relates broadly to rock drills,front housing I4 secured to the cylinder ID by but more particularly toan improved cleansing side bolts 15. Slidably mounted within the frontfluid conveying tube construction for rock drills end of the sleeve [3,there is the shank I6 of a of the reciprocatory hammer type. drill steelI! having a hole l8 extending longi- Rock drills of the fluid actuatedreciprocatudinally therethrough. In practice the rock drill 5 toryhammer type are usually equipped with a front end construction may alsoinclude a tappet tube extending longitudinally through the mal9interposed between the end of the hammer chine for conveying cleansingfluid such as water stem I2 and the shank 16 for delivering the imorcompressed air into the hollow drill steel for pacts of the hammer tothe drill steel, or that washing or blowing clean the bottom of thedrilled tappet may be eliminated to permit the direct de- 10 hole. Thistube which is generally of a quarter livery of impacts from the hammerto the drill of an inch in diameter, is of sufficient length steel. toextend partway into the hollow shank of the Secured to the upper end ofthe cylinder l0 drill steel, thereby preventing excessive leakby thebolts l5, there is a back head 20 formed age of the cleansing fluidbetween the tube and with a screw threaded bore 2| accommodating 15 theshank of the drill steel irrespective of the the head 22 of a tube 23,which head is clamped rotary and limited longitudinal movement of theagainst a packing 24 by a removable plug 25 drill steel relative to thetube. screwed within the bore 2|. Formed within the In practice however,when using drill steels plug 25 there are passages 26 for admittingformed with imperfect shanks, such as shanks cleansing fluid from thebore 2| into the tube 23. 20

having the hole therethrough eccentric relative to Also located withinthe upper end of the cylinthe tube, the end .of the tube is likely to bebent der Hi, there is a valve block 21 and a rotation by the shank, thuscausing the piston or tapmechanism including a stem 28 operatively aspetdelivering blows on the shank to literally upsociated with the hammer II for imparting rotaset the end of tube, thereby preventing the flowtion thereto, which rotation is transmitted to the 25 of the cleansingfluid through the tube and rendrill steel I! through the chuck sleevel3. dering the removal of the tube from the machine The tube 23 ispreferably made of metal and very diflicult. extends longitudinally intothe machine through It is therefore one object of this invention to thestem 28, the cylinder ID, the hammer II and 30 produce a cleansing fluidconveying tube formed the tappet I9, for limited penetration into the 0with a flexible terminal adapted to fit into the shank I6 of the drillsteel l1. With the stem drill steel shank even though the hole extending28 and at least one portion of the hammer l I, the

therethrough is located in eccentric relation reltube 23 is in close fitengagement to prevent ative to the center axis thereof. escape of themotive fluid therebetween, while Another object of this invention is toproduce the front end portion 2 9 of the tube is prefera tube of theclass above mentioned with a terably slightly reduced in diameter toprovide a minal .or extension penetrating partway into the clearancebetween the tube and the outer end drill steel shank, and adapted to bemoved thereportion of the hammer stem 12, thereby preventby withoutdanger of damaging the tube. ing any slight burr or the like which maybe Other objects of this invention will be apformed on the strikingforce of the hammer and 40 parent from the following detaileddescription around the tube, from scoring and damaging the whereincharacters of reference designate cortube.

responding parts and wherein: Referring now more particularly to theinven- Fig. 1 is a longitudinal sectional view of a rock tion, 30represents the terminal or extension of 5 drill embodying the invention.the tube 23, which is preferably made of flexible Fig. 2 is an enlargedlongitudinal view of the rubber rigidly attached to the metal tube. Toend of a cleansing fluid conveying tube conthis end, the metal tube 23is formed with a tastructed in accordance with the invention. pered end3| affording a relatively large sur- Fig. 3 is a cross sectional viewtaken in a plane face on which is glued or vulcanized the rubberindicated by line 3-3 in Fig. 2. terminal 30, which is mounted coaxiallythereon 50 Referring to the drawing, 10 represents a rock and of adiameter equal to that of the metal drill cylinder having a fluidactuated hammer tube portion adjacent thereto. The terminal 30 llreciprocable therein and formed with a splined is also provided with ahole 32 extending longistem I2 operatively associated with a chucksleeve tudinally therethrough as a continuation of the I3, which sleeveis rotatably mounted within a hole 33 formed through the tube 23. Toassure 55 and facilitate the insertion of the terminal 30 into the drillsteel shank l6, its outer end portion is preferably tapered as at 34.

In practice, the length of the rubber terminal 30 is about one inch anda half, and the length of the metal tube 23 is calculated to limit thepenetration of the terminal 30 into the drill steel shank [6 to aboutthree quarters of an inch, thereby allowing variations in the length ofthe shank l 6 without afiecting the flow ofthe cleansing fluid from thetube 23 into the drill steel H.

In operation, when the tube is used with an imperfect shank or with ashank; allowed to move laterally relative to the tube due to animperfect fit between the shank I6 and the chuck sleeve 13, the portionof the rubber terminal within the shank will move with the shank, whilethe other portion thereof between the end. of the shank I6 and the end3| of the metal tube 23 willbend or flex without damaging the tube noraffecting the flow of the cleansing fluid from the tube into the drillsteel I1.

I claim:

1. A device of the character described including a metal tube formedwith a flexible terminal of a diameter equal to the portion of said tubeadjacent thereto.

2. A device of the character describedincluding a metal tube formed witha flexible rubber terminal integrally attached thereto and of a andaterminal made of flexible material integrally attached to the taperedend portion of.

said tube.

of a hammer reciprocating therein, of a front housing and a hollow drillsteel shank slidable within said housing, of a cleansing fluid conveyingtube made of metal extending through said cylinder and hammer with oneend located within said housing falling short of said shank, and

an extension for said tube carried by the aforesaid end thereof, saidextension being made of flexible material and extending into said shank.

6. A cleansing fluid conveying tube for rock drills formed with a frontend portion of uniform diameter. including a terminal made of resilientmaterial.

7. In' a. rock drill the combination with a cylinder, of a front housingand a hollow drill steel shank s'lidable Within said housing, and arigidtube extending through said cylinder formed witlraterminal made offlexible material extend ing partway into said. drill steel shank.

8. In.a'.rock drill the combination of a cylinder with a front housinghaving a hollowdrill steel 3 shank. slidable-therein; a rigid tubewithin said cylinder fallingshort of said shank, and a flexible terminalfor said tube extending. from one end thereof into said shank.

JOHN E. RENFER.

